Cast member Balthazar Getty poses for photographers at the premiere of the film, 'Ladder 49' at The El Capitan Theatre in Los Angeles, September 14, 2004. The Touchstone Pictures movie chronicles Baltimore firefighters and opens in the US October 1st. (UPI Photo/Francis Specker)

Getty issued a statement this week stating he and wife Rosetta had separated. The announcement came after photos showing him kissing a topless Miller were published.

Getty and his wife have been married for eight years and are the parents of four young children.

"Balthazar and Rosetta were in no way separated when Balthazar began his relationship with Sienna Miller, and any implication otherwise is an absolute lie," a close friend of the married couple told People.com. "Balthazar's affair has been utterly devastating to Rosetta and her family."

A source also told the entertainment news Web site Rosetta was "blindsided" by her husband's alleged affair and claimed she only learned he was seeing Miller shortly before the incriminating photos surfaced.

Getty co-stars in the TV series "Brothers & Sisters," while Miller is best known for her roles in the films "Casanova," "Interview," "Factory Girl" and "Stardust."